I want to use the MailChimp API 3.0:
http://developer.mailchimp.com/documentation/mailchimp/reference/lists/members/#
How do I set the query string parameter for the fields since_timestamp_opt, before_timestamp_opt, since_last_changed and before_last_changed?
Is it a timestamp, something like this: 2016-03-08 17:50:41 or something else?
Can somebody give me an example?
It does need to be ISO8601 format, but even though their API shows the Timezone offset, it has no effect on the date, and the string you pass must be in UTC. You can confirm this here: https://syncwith.com/api/mailchimp/get/3-0-lists-list-id-members
The dates are stored by Mailchimp in UTC. Calling them in the current timezone with the offset won't correct for the time difference--you'll have to convert to UTC first.
